The vessel, which will bolster South Korea's submarine prosecution capabilities, is scheduled to become operational in May 2015

The Republic of Korea Navy (RoKN) has received its third Incheon-class guided-missile frigate, delivered under the Future Frigate Experimental (FFX) programme, news agency Yonhap reported on 31 December.

The agency also cited the country's Defense Acquisition Program Administration (DAPA) as saying that the vessel, named RoKS Jeonbuk (pennant number 813), will become operational in May following a four-month integration process. The warship is expected to take on roles such as maritime surveillance and anti-submarine patrol.

Jeonbuk is the third ship in the class to be produced by shipbuilder Hyundai Heavy Industries. The company was also contracted to produce the first two vessels in class, Incheon (811) and Gyeonggi (812), commissioned in January 2013 and November 2014 respectively. Another local company, STX Offshore & Shipbuilding, has been contracted to produce ships four to six.

IHS Jane's Fighting Ships notes that a further nine ships are projected to enter service by 2020. This batch of nine will be built to a substantially revised design. Some estimates suggest that a class of up to 20 vessels in total may be procured.

In August 2014 IHS Jane's reported that the frigates' six torpedo tubes will carry indigenously developed K745 Cheong Sangeo (Blue Shark) 324 mm torpedoes: these weapons have a speed in excess of 45 kt; they can also be operated in shallow waters such as the Korean peninsula's West Sea (Yellow Sea).

The Incheon-class frigates have a length of 114 m, a beam of 14 m, and a draught of 4 m. The frigates displace 3,200 tons at full load and can attain a top speed of 30 kt. They accommodate a crew of 140.

COMMENT
The effort to acquire platforms with submarine prosecution capabilities took on heightened urgency after the sinking of Po Hang-class corvette RoKS Cheonan in March 2010. A South Korean investigation concluded that the 1,200-tonne vessel was torpedoed near the Northern Limit Line (NLL) by a North Korean vessel believed to be either a Yono-class midget submarine or a Sang-O coastal submarine. Pyongyang has denied this.

The NLL, unilaterally declared by the United States military in the 1950s, is a demarcation that has not been officially recognised by North Korea. As such, the West Sea (Yellow Sea) has been the scene of repeated confrontations between the North and South, with both nations alleging incursions.

The sonar-equipped, ASW-focused Incheon-class frigates are expected to be central to the RoKN's effort to deter operations by North Korean submarines in these contested waters.